1. Field of the Invention
The invention relates to an electromagnetically-controlled valve to control an additional air amount for intervening opportunity on the amount of the fuel air mixture delivered by feed equipment of an internal combustion engine. More particularly, this invention relates to a valve of the above-mentioned type which controls a connecting pipe disposed between two zones of an intake passage. These zones are positioned upstream and downstream of a throttle valve respectively, in order to obtain an additional air flow determined according to the requirements of the operating engine.
2. Description of the Prior Art
Generally, devices are known which control additional air flow between the various parts of the feed equipment and which are placed upstream and downstream of the throttle valve. Such devices provide a by-pass channel interconnecting a part of the intake passage located upstream of the throttle valve, with a part of the intake passage located downstream of the throttle valve. Also, in the by-pass channel there is a device to control the air flow, like a fixed section housing or an adjustable section bushing, by a conic drill of an adjusting screw.
In such devices, it is impossible to vary the controlling bushing section during operation of the engine in order to adapt the additional air flow to the working requirements of the engine itself.